We'd heard a lot of good things about P&O (including here), and were looking forward to our first cruise with them. While not BAD, it certainly didn't live up to it's reputation.
Food was mediocre at best, service inconsistent, entertainment was a mixed bag with some pretty good stuff and some amateur hour quality, special interest lectures were consistently poor except for those given by the cruise director himself.
Aurora herself is beautiful, but seemed very cluttered, with shops stuck in the hallways. The mattress sagged and was lumpy, should have been replaced last year. Noisiest ship we've ever been on, we could hear both adjacent cabins plus our neighbors on the floor above. No WiFi in the cabins, I had to go to the computer room itself to log on.
Orangery cafeteria was very disorganized, often not set up for lunch by noon. They usually ran short of glasses, and when I asked for more was often greeted by a blank stare.
The pool is fresh water, which means it is very expensive to fill. So after draining it due to rough weather, they declined to refill until our next main port.
Tender service at the smaller ports was extremely inefficient compared with other ships we've been on. At one port they only put 2 boats in the water - this for 1800 passengers and a 30 minute ride to shore. Only about half the passengers that wanted even got ashore before it was time to get back aboard.
I could go on, but you get the idea. As I said, it was not so bad that we'd absolutely refuse to go again, but we'll take any other option first.
The only excellent item was the bridge classes and tournament. We're big bridge fans (not all that good, just love it), and that ended up being the only highlight of each sea day.